Effect of Nitrification Inhibitor and Cutting Heights on Degradability of Pearl Millet

Pearl millet crop has been increasingly growing in Brazilian Savanna and it is already being used as cover crop between annual crops. The plant has great forage potential, besides being a nutrient recycling plant due to its peculiar root system. This study was developed in order to assess the pearl millet nutritional value when submitted to nitrogen fertilizer. It was evaluated the effect of nitrogen fertilizer (ammonium sulfate nitrate) treated with the nitrification inhibitor 3,4-dimethyl pyrazole phosphate (DMPP) on the ruminal degradability of two pearl millets’ cultivars, under four nitrogen fertilization levels (0, 45, 90 and 180 kg ha-1) and pre-cutting heights (0.70, 0.80 and 0.90 m). The experimental design was a randomized block design in a factorial 3 × 4 (3 cutting heights × 4 nitrogen doses) with three replications. Data were submitted to analysis of variance and means were compared by Tukey test at 5% probability. The DMPP treated Nitrogen, in high doses, increased the dry matter, crude protein and neutral detergent insoluble fiber degradability in pearl millet handled at 0.90 m. The combination of fertilization with 45 or 90 kg ha-1 of nitrogen treated with DMPP, with the management of millet at 0.70 or 0.80 m did not favored the forage nutritional quality, indicating that in these treatments, the ratio between the availability of nitrogen in ammonium and nitrate forms may have been detrimental to the plants.